The U.S. space agency, NASA, has released a videotape of the crew of the doomed shuttle Columbia in their last minutes of life before the craft disintegrated one month ago.

The tape miraculously survived Columbia's breakup as it raced toward landing. It was the only one of about 250 mission tapes that was not destroyed in the disaster. Searchers recovered it among shuttle debris in Texas.

The 13 minute long video shows the seven astronauts in orange flight suits with helmets as the orbiter passed over the eastern Pacific Ocean on its way to the western coast of the United States. They begin to feel gravity again for the first time in 16 days and perform routine pre-landing operations, unaware of the impending catastrophe.

In one segment, astronaut Laurel Clark holds the camera and beckons to Indian-born crewmember Kalpana Chawla, to whom she refers by the initials KC.

Clark: "KC, can you look at the camera for a second? Look at me."Chawla: "Me?"Clark: "What, KC?"Chawla: "Oh, I just turned towards you to see what you have there."

The camera gives no hint of anything going wrong. Instead, it shows the crew laughing, talking, and sipping drinks.

Bright orange flashes light up the interior of the orbiter. These are superheated gases that glow as the shuttle makes its searing re-entry, to which pilot William McCool and commander Rick Husband refer.

McCool: "It's really [interesting]. It's a bright-orange yellow out over the nose, all around the nose."Husband: "Wait until you start seeing the swirl patterns out left and right windows."McCool: "Wow!"Husband: "[It] looks like a blast furnace."McCool: "This is amazing. It's really getting fairly bright out there."Husband: "Yeah, you definitely don't want to be outside now."

The hot gases that awed the crewmembers might figure in the orbiter's demise. The independent board investigating the disaster believes they penetrated a damaged area of the left wing and heated the orbiter beyond endurance.

Eleven minutes after the last image on the tape, mission controllers lost all contact with the crew and pieces of Columbia began falling to the ground.

The videotaping session before landing was not unusual. The commander of Columbia's previous mission last year, Scott Altman, says the activity is standard practice. "Flight deck audio and video is routinely recorded by crews during shuttle re-entry and is used for post-flight crew presentations and also as a debriefing and training tool," he said.

This tape was found on February 6, five days after the shuttle disintegrated. NASA says it waited three weeks to release it to give the families of the dead astronauts time to view it.